The Plantronics Blackwire C320-M USB headset are a easy-to-use, comfortable and durable choice for conference calls, Web-based training, and PC multimedia applications. It features monaural design with Hi-Fi stereo sound that optimizes music and video quality along with soft ear cushions ensuring maximum all day comfort. Its intuitive, inline controls let you answer/end, mute, and control the volume of PC calls. The dynamic EQ feature automatically adjusts audio for voice or multimedia use. This lightweight metal headband gives a perfect secure fit along with its digital signal processing technology and its wideband frequency optimizes audio for more natural voice quality.